The invention relates to a card top assembly for a carding machine.
In a known kind of carding machine cotton, synthetic fibres and the like, there is at least one card top bar having card top clothing, the card top clothing being fastened to the card top bar and positioned opposite to the clothing of a roller, e.g. the cylinder, and at least the regions of the clothing that face the card top bar being made of a ferrous product, especially steel.
In a known arrangement (U.S. Pat. No. 3,151,362), the card top bar consists of a back portion and a carrier body (carrier) having a foot face. Fastened to the foot face (portion that accommodates the clothing) is all-steel clothing or a clothing strip (flexible clothing) that extends in the longitudinal direction of the foot face. The all-steel clothing consists of a large number of saw-tooth wire portions arranged adjacent to one another. The clothing strip comprises a carrying element consisting of a plurality of textile layers, in which a large number of small wire hooks (clothing tips) are fastened. The regions of the steel clothings that are in each case remote from the tips are associated with the card top bar. The clothing strip is fastened along the longitudinal sides of the carrier body by means of two clamps (brackets, clips). With one end, the clamps encompass the longitudinally oriented edge regions of the clothing strip and with their other end engage in recesses in the carrier body. In practice, the clamps consist of a sheet metal strip, one longitudinal edge of which is cut into the textile material. On assembly, the textile material of the clothing strip is fastened to the carrier body of the card top bar in a positive fit under considerable stress. In the process, the clamps exert tensile forces in such a manner that the textile material is deformed convexly away from the foot face, so that the clothing tips facing outwards are also, undesirably, arranged on a convex-shaped envelope. When not in use, the resulting card top assembly has a precision of 0.05 mm in height and evenness. In use, the differences in height in the assembly increase to approximately 0.2 mm. Sharpening the clothing on the machine improves precision only insignificantly. After a throughput of approximately 400 t of fibre material, the card top clothing is so worn that it has to be replaced. In order to dismantle the sheet metal staples, the card top bar is clamped and the positive fit is reversed by means of a lever and pincers. The considerable forces that occur during assembly and dismantling have a deleterious effect on the dimensional stability of the card top bar.
It is an aim of the invention to provide an arrangement of the type described at the beginning that avoids or mitigates the disadvantages mentioned, makes it possible, especially in simple manner, to obtain a clothed card top bar that is dimensionally stable and enables simpler and more rapid reclothing (clothing replacement).